【摘要】 应用鱼类主要组织相容性复合体(MHC)基因来探讨鱼类种群间遗传结构,寻找分子遗传标记。根据已报道的鲤鱼MHCⅠ类基因序列,设计了一对特异性引物,从兴国红鲤、荷包红鲤、玻璃红鲤及瓯江彩鲤基因组DNA中扩增了编码MHCⅠ类分子α2链的基因片段,并进行克隆、测序。结果表明,(1)编码MHCⅠ类分子α2链的基因多态性较为丰富,234bp长度中有106个变异位点,多态位点百分率达45.3%;荷包红鲤的基因序列与其它3群体红鲤有显著差异;(2)由编码MHCⅠ类分子α2链的基因和氨基酸序列构建的系统进化树一致,兴国红鲤与瓯江彩鲤关系较近,属于同一进化支,玻璃红鲤和荷包红鲤分别属于另外两个不同的进化支,荷包红鲤是较为特化的群体;(3)多态性丰富的编码MHCⅠ类分子α2链的基因,适宜作为鲤鱼不同群体的分子遗传标记。更多还原

【Abstract】 The major histocompatibility complex (MHC) of fish was used to study the genetic structure as a molecular genetic marker of four populations of red common carp. Based on reported common carp MHC classⅠgene sequences, a pair of specific primers was designed, MHC classⅠmolecular α2 gene fragments were amplified from Xingguo red common carp (Cyprinus carpio var. singguonensis), purse red common carp (C. carpio var. wuyuanensis), glass red common carp (C. carpio var. wananensis), and Oujiang color common carp (C. carpio var. color), then cloned and sequenced. The polymorphism of encoded MHC classⅠmolecular α2 chain gene was rich, with 106 variable loci in 234bp in length. The percentage of polymorphism was 45.3%, among the four populations, purse red common carp was significantly different from the other red common carps. The phylogenetic trees constructed by encoded MHC classⅠmolecular α2 chain gene and its amino acid sequences indicated identically, and the relationship between Xingguo red common carp and Oujiang color common carp was closer, belonging to one evolutionary branch, whereas glass red common carp and purse red common carp belonged to the other two different evolutionary branches respectively. The purse red common carp is a more specialized group. The rich polymorphism of encoded MHC classⅠ molecular α2 chain gene is suitable as a molecular genetic marker for different populations of common carp.更多还原